This study examined the relationship between mental toughness and failure attributions in high level swimmers. Participants were 80, (M age=21.64, S.D: 4.96 years) regional and national level swimmers who were currently competing. Participants were asked to recall a perceived failure in the previous four weeks, fill in the controllability, stability, globality and universality attribution measure (CSGU) and eight weeks later complete the mental toughness questionnaire-48 (MTQ48). Multiple regression analysis found a significant effect of mental toughness and stability on controllability (ΔR2 = 0.042, p = 0.021) when the generalizability dimensions were added to the model. Separate multiple regression analysis for both genders, revealed that males mental toughness and stability predicted controllability (ΔR2 = 0.200, p = 0.029) compared to females mental toughness and universality (ΔR2 = 0.080, p = 0.027) predicting controllability. In conclusion the present study found evidence for mental toughness predicting controllability attributions following competitive failure for a group of high level male and female swimmers. Gender differences were found in how the generalizability attributions predicting controllability. Findings are discussed in terms of mental toughness and the generalizability dimensions predicting controllability attributions in response to competitive failure and suggestions to examine the relationship further.